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Matthew S Grober - One of the best experts on this subject based on the ideXlab platform.
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Diurnal patterns and sex differences in cortisol, 11-Ketotestosterone, testosterone, and 17β-estradiol in the bluebanded goby (Lythrypnus dalli)
General and Comparative Endocrinology, 2007Co-Authors: Varenka Lorenzi, Ryan L. Earley, Edmund W. Rodgers, D.r. Pepper, Matthew S GroberAbstract:Abstract The primary goals of this study were to evaluate diurnal patterns of and sex differences in the levels of cortisol, 11-Ketotestosterone, testosterone, and 17β-estradiol in the sex-changing bluebanded goby Lythrypnus dalli. Steroid hormones were collected from water samples and analyzed by enzyme immunoassay. During the breeding season, hormones were sampled from both males and females at seven time points between 0600 and 2000 h. When comparing each time point separately, there were significant overall time effects for cortisol and 17β-estradiol. Cortisol concentrations were lowest at the 0800–1000 h sampling point and showed a qualitative peak in late morning (1000–1200 h). Concentrations of 17β-estradiol were elevated at the last sampling point (1800–2000 h). Broader temporal trends were revealed for testosterone and 11-Ketotestosterone concentrations, both of which were elevated in the morning. There were no sex differences in overall hormone concentrations or temporal profiles for cortisol, 11-Ketotestosterone, or testosterone. Males and females showed similar diurnal patterns of 17β-estradiol but females had significantly higher water-borne 17β-estradiol levels than males. The results show the presence of diurnal changes in steroid hormone levels in male and female bluebanded gobies. The lack of sex differences in androgens suggests that males of this species, and perhaps other bi-directional sex-changing species in which males do not exhibit prominent secondary sexual characteristics, do not require persistent elevations in 11-Ketotestosterone or testosterone to maintain the male phenotype. Although the role of 17β-estradiol in maintaining sex differences in sexually plastic species is unclear, our results suggest that, of the hormones measured, 17β-estradiol has the greatest potential for future studies interested in this question.
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Elevated 11-Ketotestosterone during paternal behavior in the Bluebanded goby (Lythrypnus dalli).
Hormones and Behavior, 2006Co-Authors: Edmund W. Rodgers, Ryan L. Earley, Matthew S GroberAbstract:The relationship between androgens and paternal behavior is not straightforward, potentially because of the diversity of tasks a male must undertake to maximize reproductive success, notably alternating between courtship, aggression, and offspring care. In some species, these events are separated in time, but in others they are coincident. The endocrine profiles of species that simultaneously court, parent, and defend a nest, such as male bluebanded gobies (Lythrypnus dalli), are not well understood. We sampled a potent fish androgen, 11-Ketotestosterone (KT), at different life history stages (experienced parenting males, experienced males not actively parenting, inexperienced males with their first clutch, and females), to examine this relationship. We found that experienced parenting L. dalli males have the highest KT levels of any group, while none of the other groups differed significantly. Males showed elevated KT levels when they had eggs compared to when they did not. Our data suggest that KT facilitates at least some aspects of parental care in L. dalli.
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11 ketotestosterone inhibits the alternative mating tactic in sneaker males of the peacock blenny salaria pavo
Brain Behavior and Evolution, 2001Co-Authors: Rui Filipe Oliveira, Adelino V M Canario, Luís Alberto Carneiro, David Goncalves, Matthew S GroberAbstract:In the peacock blenny, Salaria pavo , a species with courtship sex-role reversal, smaller, younger males mimic the courtship behavior and the nuptial coloration of females in order t
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Effects of 11‐ketotestosterone on genital papilla morphology in the sex changing fish Lythrypnus dalli
Journal of Fish Biology, 2000Co-Authors: S. L. Carisle, Luís Alberto Carneiro, Adelino V M Canario, Rui Filipe Oliveira, S. K. Marxer-miller, Matthew S GroberAbstract:Five days after implantation with 11-Ketotestosterone (KT) female Lythrypnus dalli exhibited elevated urinary KT levels and male-like genital papilla morphology. Papilla length increased, width decreased, and length : width ratio increased. Control fish exhibited increases in papilla length, and length : width ratio on day 3, but not on day 5. Changes in the total area of the papilla were not statistically significant. It is suggested that KT mediates genital papilla morphology rapidly and thus may be a useful indicator of circulating KT in L. dalli.
Eduardo N Barata - One of the best experts on this subject based on the ideXlab platform.
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11 ketotestosterone stimulates putative sex pheromone production in the male peacock blenny salaria pavo risso 1810
Biology of Reproduction, 2008Co-Authors: Adelino V M Canario, Rui M Serrano, Orlando Lopes, Peter C Hubbard, Jorge Araujo, Eduardo N BarataAbstract:Abstract Male peacock blennies (Salaria pavo) release odors from their anal glands and, possibly, from their gonads that attract reproductive females. The current study investigated the effects of 11-Ketotestosterone (KT) on development of the anal glands, testes, and accessory testicular organs as well as the subsequent olfactory potency of their secretions. After 3 wk of KT treatment (5 mg/kg in silastic implants), clusters of cells secreting neutral mucins differentiated in the anal gland of all treated males, whereas this occurred in only one control male. Secretions by anal glands from KT-treated males elicited greater olfactory responses, as assessed by electro-olfactography, than those from controls. Treatment with KT stimulated testicular gland growth and sialomucin secretion but had no clear effect on the germinal region of the testis; KT also stimulated enlargement of, and fluid secretion in, the blind pouches (paired evaginations of the spermatic ducts). Secretions by the testes and fluid in bl...
Adelino V M Canario - One of the best experts on this subject based on the ideXlab platform.
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Social context may affect urinary excretion of 11-Ketotestosterone in African cichlids
Behaviour, 2020Co-Authors: Katharina Hirschenhauser, Adelino V M Canario, Michael Taborsky, Rui Filipe OliveiraAbstract:Summary We previously investigated the androgen responsiveness of males to simulated partner and territory intrusions in five African cichlid species (Neolamprologus pulcher, Lamprologus callipterus, Tropheus moorii, Pseudosimochromis curvifrons, Oreochromis mossambicus; Hirschenhauser et al., 2004). Here we re-analysed data on 11-Ketotestosterone (11-KT) levels in holding water to compare the free (presumably from the gills) and conjugated (presumably from urine and faeces) 11-KT fractions. We sampled (i) pre-test baseline control levels from individual males in social isolation and (ii) response levels released after social interactions, either with an ovulating female or a male territory intruder. In four out of five species, conjugated metabolites contributed to the observed total 11-KT responses in water during social context, which was particularly apparent in peak responsive individuals exposed to male intruders. Thus, in water from males sampled in isolation immunoreactive 11-KT seemed to derive both from gills and urine, whereas the urinary 11-KT component apparently increased in the social context, particularly when a male was challenged by a same-sex intruder. These results suggest that (i) the social context may affect urine release patterns of males and (ii) 11KT data acquired by using fish-holding water may not simply reflect the passive transmission of steroid hormones via the gills.
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11 ketotestosterone stimulates putative sex pheromone production in the male peacock blenny salaria pavo risso 1810
Biology of Reproduction, 2008Co-Authors: Adelino V M Canario, Rui M Serrano, Orlando Lopes, Peter C Hubbard, Jorge Araujo, Eduardo N BarataAbstract:Abstract Male peacock blennies (Salaria pavo) release odors from their anal glands and, possibly, from their gonads that attract reproductive females. The current study investigated the effects of 11-Ketotestosterone (KT) on development of the anal glands, testes, and accessory testicular organs as well as the subsequent olfactory potency of their secretions. After 3 wk of KT treatment (5 mg/kg in silastic implants), clusters of cells secreting neutral mucins differentiated in the anal gland of all treated males, whereas this occurred in only one control male. Secretions by anal glands from KT-treated males elicited greater olfactory responses, as assessed by electro-olfactography, than those from controls. Treatment with KT stimulated testicular gland growth and sialomucin secretion but had no clear effect on the germinal region of the testis; KT also stimulated enlargement of, and fluid secretion in, the blind pouches (paired evaginations of the spermatic ducts). Secretions by the testes and fluid in bl...
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11 ketotestosterone inhibits the alternative mating tactic in sneaker males of the peacock blenny salaria pavo
Brain Behavior and Evolution, 2001Co-Authors: Rui Filipe Oliveira, Adelino V M Canario, Luís Alberto Carneiro, David Goncalves, Matthew S GroberAbstract:In the peacock blenny, Salaria pavo , a species with courtship sex-role reversal, smaller, younger males mimic the courtship behavior and the nuptial coloration of females in order t
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Effects of 11‐ketotestosterone on genital papilla morphology in the sex changing fish Lythrypnus dalli
Journal of Fish Biology, 2000Co-Authors: S. L. Carisle, Luís Alberto Carneiro, Adelino V M Canario, Rui Filipe Oliveira, S. K. Marxer-miller, Matthew S GroberAbstract:Five days after implantation with 11-Ketotestosterone (KT) female Lythrypnus dalli exhibited elevated urinary KT levels and male-like genital papilla morphology. Papilla length increased, width decreased, and length : width ratio increased. Control fish exhibited increases in papilla length, and length : width ratio on day 3, but not on day 5. Changes in the total area of the papilla were not statistically significant. It is suggested that KT mediates genital papilla morphology rapidly and thus may be a useful indicator of circulating KT in L. dalli.
Glen Van Der Kraak - One of the best experts on this subject based on the ideXlab platform.
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fathead minnow pimephales promelas reproduction is impaired when exposed to a naphthenic acid extract
Aquatic Toxicology, 2012Co-Authors: Richard J Kavanagh, Richard A Frank, Rozlyn F Young, Keith R Solomon, Kent B Burnison, Phillip M. Fedorak, Glen Van Der KraakAbstract:Abstract Previous studies have demonstrated that oil sands process-affected water (OSPW) impairs the reproduction of fish and that naphthenic acids (NAs), a natural constituent of oil sands, are suspected of being responsible. This study evaluates the potential impact of NAs on the reproduction of adult fathead minnows ( Pimephales promelas ) under laboratory conditions. Fathead minnows exposed to a 10 mg/l naphthenic acid extract (NAE) for 21 days spawned fewer eggs and males had reduced expression of secondary sexual characteristics. Male fathead minnows exposed to a 5 mg/l NAE had lower plasma levels of 11-Ketotestosterone whereas those exposed to a 10 mg/l NAE had lower concentrations of both testosterone and 11-Ketotestosterone. Since OSPW also contains high concentrations of salts, this study also investigated whether they modify the toxicity of NAEs. Spawning was significantly reduced in fathead minnows exposed to a 10 mg/l NAE alone and in combination with NaHCO 3 (700 mg/l), typical of concentrations in OSPW . Interestingly, the addition of NaHCO 3 reduced the inhibitory effects of the NAE on the numbers of reproductive tubercles and plasma testosterone levels. Further studies showed that NaHCO 3 acted by reducing the uptake of the NAE to the fish. NaHCO 3 but not NaCl or Na 2 SO 4 reduced the acute toxic effects of the NAE on fathead minnow embryo and larvae mortality. Collectively, these studies show that the NAs in OSPW have the potential to negatively affect reproduction in fathead minnows and that HCO 3 − reduces the acute and chronic toxicity of NAs.
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fathead minnow pimephales promelas reproduction is impaired in aged oil sands process affected waters
Aquatic Toxicology, 2011Co-Authors: Richard J Kavanagh, Richard A Frank, Ken D Oakes, Mark R Servos, Rozlyn F Young, Michael D Mackinnon, Keith R Solomon, George D Dixon, Phillip M. Fedorak, Glen Van Der KraakAbstract:Abstract Large volumes of fluid tailings are generated during the extraction of bitumen from oil sands. As part of their reclamation plan, oil sands operators in Alberta propose to transfer these fluid tailings to end pit lakes and, over time, these are expected to develop lake habitats with productive capabilities comparable to natural lakes in the region. This study evaluates the potential impact of various oil sands process-affected waters (OSPW) on the reproduction of adult fathead minnow (Pimephales promelas) under laboratory conditions. Two separate assays with aged OPSW (>15 years) from the experimental ponds at Syncrude Canada Ltd. showed that water containing high concentrations of naphthenic acids (NAs; >25 mg/l) and elevated conductivity (>2000 μS/cm) completely inhibited spawning of fathead minnows and reduced male secondary sexual characteristics. Measurement of plasma sex steroid levels showed that male fathead minnows had lower concentrations of testosterone and 11-Ketotestosterone whereas females had lower concentrations of 17β-estradiol. In a third assay, fathead minnows were first acclimated to the higher salinity conditions typical of OSPW for several weeks and then exposed to aged OSPW from Suncor Energy Inc. (NAs ∼40 mg/l and conductivity ∼2000 μS/cm). Spawning was significantly reduced in fathead minnows held in this effluent and male fathead minnows had lower concentrations of testosterone and 11-Ketotestosterone. Collectively, these studies demonstrate that aged OSPW has the potential to negatively affect the reproductive physiology of fathead minnows and suggest that aquatic habitats with high NAs concentrations (>25 mg/l) and conductivities (>2000 μS/cm) would not be conducive for successful fish reproduction.
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Differential effects of 17β-estradiol and 11-Ketotestosterone on the endocrine stress response in zebrafish (Danio rerio).
General and Comparative Endocrinology, 2010Co-Authors: Meghan L.m. Fuzzen, Nicholas J. Bernier, Glen Van Der KraakAbstract:Abstract Sexually dimorphic stress responses are present in species across all vertebrate taxa and it has been suggested that these effects are mediated by circulating sex steroids. While a few species of fish have been identified as having a sexually dimorphic stress response, there is conflicting evidence as to the effects of sex steroids on the stress axis. In this study, we tested whether zebrafish exhibit a sexually dimorphic cortisol stress response and whether 17β-estradiol (E2) or 11-Ketotestosterone (11KT) modulate the activity of the hypothalamic-pituitary-interrenal (HPI) axis. To accomplish this, we quantified the whole body cortisol response to a physical stressor, cortisol release in vitro , and the expression of key HPI axis regulating genes of control and E2- or 11KT-exposed zebrafish. Under control conditions no dimorphisms in the HPI axis were apparent at rest or in response to a standardized stressor. In contrast, E2-exposure blunted the cortisol response of male fish in vivo and in vitro and as well as corticotropin-releasing factor ( crf ) expression in the pre-optic area (POA) of the brain. While the expression of some interrenal genes was suppressed by E2-exposure, these changes occurred in both male and female zebrafish. 11KT-exposure increased whole-body cortisol of males at rest and vortex-exposed females, but had no impact on the rate of cortisol synthesis in vitro or on POA crf expression. Therefore, while we found no evidence that zebrafish exhibit a sexually dimorphic cortisol stress response, both E2 and 11KT can modulate the activity of the HPI axis in this species and do so via different mechanisms.
Rui Filipe Oliveira - One of the best experts on this subject based on the ideXlab platform.
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Social context may affect urinary excretion of 11-Ketotestosterone in African cichlids
Behaviour, 2020Co-Authors: Katharina Hirschenhauser, Adelino V M Canario, Michael Taborsky, Rui Filipe OliveiraAbstract:Summary We previously investigated the androgen responsiveness of males to simulated partner and territory intrusions in five African cichlid species (Neolamprologus pulcher, Lamprologus callipterus, Tropheus moorii, Pseudosimochromis curvifrons, Oreochromis mossambicus; Hirschenhauser et al., 2004). Here we re-analysed data on 11-Ketotestosterone (11-KT) levels in holding water to compare the free (presumably from the gills) and conjugated (presumably from urine and faeces) 11-KT fractions. We sampled (i) pre-test baseline control levels from individual males in social isolation and (ii) response levels released after social interactions, either with an ovulating female or a male territory intruder. In four out of five species, conjugated metabolites contributed to the observed total 11-KT responses in water during social context, which was particularly apparent in peak responsive individuals exposed to male intruders. Thus, in water from males sampled in isolation immunoreactive 11-KT seemed to derive both from gills and urine, whereas the urinary 11-KT component apparently increased in the social context, particularly when a male was challenged by a same-sex intruder. These results suggest that (i) the social context may affect urine release patterns of males and (ii) 11KT data acquired by using fish-holding water may not simply reflect the passive transmission of steroid hormones via the gills.
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Forebrain Transcriptional Response to Transient Changes in Circulating Androgens in a Cichlid Fish.
G3: Genes Genomes Genetics, 2020Co-Authors: Ana S. Félix, Sara D. Cardoso, António Roleira, Rui Filipe OliveiraAbstract:It has been hypothesized that androgens respond to the social interactions as a way to adjust the behaviour of individuals to the challenges of the social environment in an adaptive manner. Therefore, it is expected that transient changes in circulating androgen levels within physiological scope should impact the state of the brain network that regulates social behavior, which should translate into adaptive behavioural changes. Here, we examined the effect that a transient peak in androgen circulating levels, which mimics socially driven changes in androgen levels, has on the forebrain state, which harbors most nuclei of the social decision-making network. For this purpose, we successfully induced transient changes in circulating androgen levels in an African cichlid fish (Mozambique tilapia, Oreochromis mossambicus) commonly used as a model in behavioral neuroendocrinology by injecting 11-Ketotestosterone or testosterone, and compared the forebrain transcriptome of these individuals to control fish injected with vehicle. Forebrain samples were collected 30 min and 60 min after injection and analyzed using RNAseq. Our results showed that a transient peak in 11-Ketotestosterone drives more accentuated changes in forebrain transcriptome than testosterone, and that transcriptomic impact was greater at the 30 min than at the 60 min post-androgen administration. Several genes involved in the regulation of translation, steroid metabolism, ion channel membrane receptors, and genes involved in epigenetic mechanisms were differentially expressed after 11-Ketotestosterone or testosterone injection. In summary, this study identified specific candidate genes that may regulate socially driven changes in behavioural flexibility mediated by androgens.
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Androgens and Immune Function in Male Alternative Reproductive Morphotypes of the Peacock Blenny Salaria pavo
Ethology, 2009Co-Authors: Rui Filipe OliveiraAbstract:Species with alternative reproductive tactics offer the opportunity to analyse how behavioural and morphological traits are tuned to produce successfully competing phenotypes within one sex. In the teleost fish Salaria pavo, alternative reproductive tactics are sequential. The older ornamented males compete for access to females by guarding a cavity to which they attract females to spawn. Ornamented males that are found without a nest are called ‘floaters’. Younger mature males which are too small to compete with nest-holders attempt to ‘sneak’ as female mimics into successful nests and release their sperm to fertilize freshly spawned eggs. The alternative tactics in S. pavo are associated with different levels of the androgens testosterone and 11-Ketotestosterone, which have been found to suppress immune function in several teleost fish. A field study was carried out to analyse the relationship between these reproductive tactics, androgens and blood levels of lymphocytes as a monitoring method of immune function. We expected highest investment in the immune system in sneakers because these have the lowest androgen levels and functionally because investing in self-maintenance increases their future prospect to switch tactic and to reproduce as a nest-holder. Indeed, the relative count of lymphocytes correlated negatively with body size and thus was highest in sneakers and lowest in nest-holders. In concordance, 11-Ketotestosterone and testosterone levels were found to be higher in floaters and nest-holders than in sneakers. However, no correlation was found between individual levels of testosterone or 11-Ketotestosterone and lymphocytes. Thus, a trade-off between reproductive traits associated with high androgen levels and immunocompetence might exist at the level of alternative tactics but this might not be explained by acute immunosuppressive effects of circulating androgens. Ethology
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11 ketotestosterone inhibits the alternative mating tactic in sneaker males of the peacock blenny salaria pavo
Brain Behavior and Evolution, 2001Co-Authors: Rui Filipe Oliveira, Adelino V M Canario, Luís Alberto Carneiro, David Goncalves, Matthew S GroberAbstract:In the peacock blenny, Salaria pavo , a species with courtship sex-role reversal, smaller, younger males mimic the courtship behavior and the nuptial coloration of females in order t
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Effects of 11‐ketotestosterone on genital papilla morphology in the sex changing fish Lythrypnus dalli
Journal of Fish Biology, 2000Co-Authors: S. L. Carisle, Luís Alberto Carneiro, Adelino V M Canario, Rui Filipe Oliveira, S. K. Marxer-miller, Matthew S GroberAbstract:Five days after implantation with 11-Ketotestosterone (KT) female Lythrypnus dalli exhibited elevated urinary KT levels and male-like genital papilla morphology. Papilla length increased, width decreased, and length : width ratio increased. Control fish exhibited increases in papilla length, and length : width ratio on day 3, but not on day 5. Changes in the total area of the papilla were not statistically significant. It is suggested that KT mediates genital papilla morphology rapidly and thus may be a useful indicator of circulating KT in L. dalli.
